/**
 * $Id: XmlUtils.java,v 1.1 2012-01-13 12:26:15 david Exp $
 * Copyright (c) 2007-2012, JGraph Ltd
 */
package com.kg.rails.component.editor.util;

import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.xml.sax.InputSource;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import java.io.StringReader;
import java.io.StringWriter;

/**
 * Contains various XML helper methods for use with Graph.
 */
public class XmlUtils {
    /**
     * Returns a new document for the given XML string.
     *
     * @param xml String that represents the XML data.
     * @return Returns a new XML document.
     */
    public static Document parseXml(String xml) {
        try {
            DocumentBuilderFactory docBuilderFactory = DocumentBuilderFactory.newInstance();
            DocumentBuilder docBuilder = docBuilderFactory.newDocumentBuilder();

            return docBuilder.parse(new InputSource(new StringReader(xml)));
        } catch (Exception e) {
            e.printStackTrace();
        }

        return null;
    }

    /**
     * Returns a string that represents the given node.
     *
     * @param node Node to return the XML for.
     * @return Returns an XML string.
     */
    public static String getXml(Node node) {
        try {
            Transformer tf = TransformerFactory.newInstance().newTransformer();

            tf.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
            tf.setOutputProperty(OutputKeys.ENCODING, "UTF-8");

            StreamResult dest = new StreamResult(new StringWriter());
            tf.transform(new DOMSource(node), dest);

            return dest.getWriter().toString();
        } catch (Exception e) {
            // ignore
        }

        return "";
    }
}